Poweshiek Skipperling Head-Start Project

This loss of this prairie habitat has resulted in the dramatic decline of several highly specialized grassland species including the Poweshiek skipperling. This small orange-brown skipper may go unnoticed by most, but it is dependent on tall- and mixed-grass prairie habitat.

The Assiniboine Park Zoo is collaborating with Minnesota Zoo’s Prairie Butterfly Conservation Program, the Nature Conservancy of Canada, and University of Winnipeg researchers to help establish a head-starting program for grassland specialist butterflies that are at risk of extinction. Head-start programs bring animals or young in from the wild and raise them until they are old enough to survive on their own. They are then released into the wild to increase the population size or re-establish the population in areas where they have gone extinct.

About the Species

The Poweshiek skipperling is active in its adult form for only three or four weeks in June and July. Adult skippers breed, and females lay eggs on host plants, which are typically grasses and sedges found in tall-grass prairie. When the eggs hatch, caterpillars emerge and feed on grasses, before spending the winter at the base of plants under the snow. The following spring, the caterpillar will form a chrysalis, and emerge as an adult that June or July, and the cycle repeats.

Less than 1% of the native prairie habitat that once covered Manitoba remains to this day. This habitat is critical for the Poweshiek skipperling as well as other species that depend on it. Most of this land has been converted to agriculture. Other threats include climate change, pesticide use, over grazing, fire, and invasive species.

Conservation

The University of Winnipeg, The Nature Conservancy of Canada, Environment and Climate Change Canada, Manitoba Sustainable Development, and Assiniboine Park Zoo are working together to form the Canadian section of the Poweshiek Protection Team. They are actively working on recovery and research projects that will help us understand and supplement the wild population that remains.

Assiniboine Park Zoo is the location of the captive rearing and head-starting program for the Poweshiek skipperling beginning this summer, in 2017. The Conservation and Research team have dedicated staff and volunteers who will raise the skippers from egg to adulthood over the year. On recommendation of local and international experts, captive rearing operations were established in 2016 with a surrogate species, the Garita skipperling. The goal of the surrogate program is to develop the skills, techniques, and infrastructure to use for rearing Poweshiek skipperlings in 2017. The goal of this program, the butterflies in this program will be reared from eggs and released into the wild as adults to help Manitoba populations recover.

Research

Dr. Richard Westwood at the University of Manitoba has been studying the Poweshiek skipperling in Manitoba for several years, documenting population trends, habitat preferences, nectaring sources, and assessing suitability of habitat.

A graduate student is set to start research in September of 2017 on modelling the suitability of potential release sites of adult Poweshiek skipperlings from the captive breeding program. They will also investigate microclimate variations in the field compared to the captive rearing program.